Open-source AI code review
arnx investigates code changes, generates and runs tests for suspected bugs, and lets you keep confirmed findings as regression checks.
Your agent writes the code.
arnx checks the behavior.
arnx 0.1.0 · Bring your own model keys, or use arnx cloud.
Python + Postgres / real review
A page limit dropped callouts while the polling state advanced.
The generated tests reproduced the failure. The owner accepted the finding and fixed the code.
Read the case study ↗Summary of a recorded run; not terminal output.
Rust is early and our least-tested runner. First setup compiles dependencies and test targets into an image that can take several GB. Try your crate and tell us what breaks ↗
01 / A real review
On a Python pipeline backed by Postgres, generated tests reproduced an inverted calculation, lost callouts beyond a page limit, and stale prices used in evaluation.
The owner marked 18 findings real. Their coding agent changed the product code; accepted test files stayed unchanged after acceptance.
Read the full case study ↗FINAL ACCEPTED-TEST CHECK
One owner-run case on a tuned development branch. Two known issues were missed. The counts describe the final test run, not bug-detection accuracy. Private source and raw execution logs are not published.
02 / How arnx works
Understand the project, propose a Docker test environment, and run the existing suite. Inspect the configuration before approval.
arnx setup
Investigate the diff, generate targeted tests, and run them. Read the failures, open questions, and coverage gaps.
arnx review
Validate meaningful findings and keep their tests. You or your coding agent make the fix.
arnx accept <id>
Rerun accepted regression tests in Docker without new model calls. Review and commit the tests with the fix.
arnx check
03 / Why executable evidence matters
A review comment identifies a possible problem. An executed test gives you inputs, an expected result, and a failure you can investigate.
A test can misunderstand intent, depend on a brittle fixture, or fail at setup. Repetition and a second model do not replace developer review.
Accepted tests remain local files. Use
arnx check after the fix and on later changes, with
no additional model inference cost.
04 / Choose your setup
Tool calls, Docker tests, the before/after check, and report generation run on your machine. arnx cloud receives the diff, the files the agent reads, the tests it writes and their output, then passes them to its model providers. Read the data and execution boundaries.
05 / Built with developers
Report a bug, request framework support, or help make a generated test more useful. A small reproduction and clear expected behavior are a good place to start.
Keep the evidence
arnx 0.1.0 · Bring your own model keys, or use arnx cloud.